How to update esophageal masses imaging using literature review (MRI and CT features)

Abstract MRI offers new opportunities for detailed visualization of the different layers of the esophageal wall, as well as early detection and accurate characterization of esophageal lesions. Staging of esophageal tumors including extramural extent of disease, and status of the adjacent organ can also be performed by MRI with higher accuracy compared to other imaging modalities including CT and esophageal endoscopy. Although MDCT appears to be the primary imaging modality that is indicated for preoperative staging of esophageal cancer to assess tumor resectability, MDCT is considered less accurate in T staging. This review aims to update radiologists about emerging imaging techniques and the imaging features of various esophageal masses, emphasizing the imaging features that differentiate between esophageal masses, demonstrating the critical role of MRI in esophageal masses. Critical relevance statement MRI features may help differentiate mucosal high-grade neoplasia from early invasive squamous cell cancer of the esophagus, also esophageal GISTs from leiomyomas, and esophageal malignant melanoma has typical MR features. Key Points MRI can accurately visualize different layers of the esophagus potentially has a role in T staging. MR may accurately delineate esophageal fistulae, especially small mediastinal fistulae. MRI features of various esophageal masses are helpful in the differentiation. Graphical Abstract

Lesion shows homogeneous isodensity on contrast-enhanced CT image (a).The lesion is heterogenous hyperintense on pre-contrast T1-weighted image (b), no definite enhancing mass (white arrow) (c) with intensely enhancing stalk (yellow arrow) on contrast-enhanced T1-weighted image (d), hypo-and slightly hyperintensity on T2-weighted image (e), restricted diffusion and lower ADC value (mean: 1.595x10 -3 mm 2 /s) (f, g).The lesion is showed in oesophagoscope (h) and endoscopic ultrasonography (i), with features of melanin or recent bleeding.H&E-stained section at ×100 microscopy confirms the presence of esophageal malignant melanoma with diffuse proliferation of round cells, non-cohesive, with intracytoplasmic melanic pigment (green arrow) (j).

Figure S2 .
Figure S2.Esophageal leiomyoma in a 45-year-old woman.There is iso attenuating mass (white arrow) on contrast enhanced CT image (a).The mass is, isointense to muscularis propria on T2-weighted image with similar intensity to muscularis propria (yellow arrow) (b), slightly enhancing on contrast enhanced T1-weighted image (c), no diffusion restriction (d), and iso ADC value to muscularis propria (mean: 1.035x10 - 3 mm 2 /s) (e).Oesophagoscope (f) and endoscopic ultrasonography (g) shows this submucous protrusion lesion.H&E-stained section at × 200 microscopy confirms the presence of leiomyoma with rod cell nucleus (blue arrow) (h).

Figure S4 .
Figure S4.Esophageal schwannoma in a 71-year-old man.Axial CT images (a, b) and multiplanar reformation CT images (c, d) show a large lesion of the esophagus with heterogenous enhancement (white arrow), and a second sessile mass with thinning enhanced mucosa (yellow arrow) on contrast-enhanced CT images.Axial CT image show peritumoral lymph node enlargement (green arrow, e).Oesophagoscope (f) and endoscopic ultrasonography (g) shows the lesion almost blocks the entire esophagus.H&E-stained section at ×200 microscopy confirms the presence of schwannoma with shuttle tumor cells, and S-100 (schwannoma marker) (+), SOX-10 (schwannoma marker) (+) (h).

Figure S5 .
Figure S5.Esophageal lipoma images in a 58-year-old woman.Lesion shows low attenuation and unenhanced mass (yellow arrow) after contrast injection on CT image (a), submucosal high intensity mass (yellow arrow) on both T1-and T2weighted images (b, c), unenhanced low intensity mass after contrast injection on fat saturation T1-weighted image.Oesophagoscope (f) and endoscopic ultrasonography (g) shows this little submucous protrusion lesion, endoscopic resection is performed subsequently to show adipose tissue (g).

Figure S6 .
Figure S6.Esophageal hemangioma in a 58-year-old woman.The lesion (white arrow) shows similar enhancement to mucosa (blue arrow) with strong homogenous enhancing stalk (yellow arrow) on contrast-enhanced T1-weighted image (a, b).The mass is moderate hyperintense on T2-weighted image (c).CT shows a poorly defined enhancing mass (white arrow) after contrast injection without definite pedicle (d).PET/CT shows the mass with SUV value of 7.1 (e).Oesophagoscope (f) and endoscopic ultrasonography (g) shows the lesion.Intraoperative photography showed the stalk of the mass (h).It was confirmed to be granulation tissue-type hemangioma histopathologically.

Figure S7 .
Figure S7.Fungal infected cyst images in a 23-year-old woman.Lesion shows a submucosal homogenous unenhanced mass (white arrow) after contrast injection on CT image (a), isointensity on T1-weighted image (b), moderate heterogeneous hyperintensity, which is slightly higher than mucosa (yellow arrow) on T2-weighted image (c), no diffusion restriction (d, e), and homogenous unenhanced mass after contrast injection on T1-weighted image (f).Oesophagoscope (g) and endoscopic ultrasonography (h) shows this submucous protrusion lesion.Fungal filaments can be seen on the esophageal lump puncture fluid base (H&E-stained section, i), which shows fungal mycelium (blue arrow) within the stacked squamous epithelium (purple arrow).